All of the following methods are anti-larval measures, except -

Correct option is D

Ans. (d) Malathion
Explanation:
Anti-larval measures are methods used to control mosquito larvae and prevent their development into adult mosquitoes, thereby reducing mosquito-borne diseases like malaria, dengue, and filariasis.
✅ Options (a), (b), and (c) are anti-larval measures, while (d) Malathion is not.
Anti-Larval Measures:
1. Intermittent Irrigation (✅ Anti-Larval Measure)
· Periodic drying of water bodies (paddy fields, stagnant water) to disrupt mosquito breeding.
2. Paris Green (✅ Anti-Larval Measure)
· A chemical larvicide (copper acetoarsenite) that kills mosquito larvae in water.
· Used in malaria control programs.
3. Gambusia affinis (Mosquito Fish) (✅ Anti-Larval Measure)
· A biological control method → Gambusia affinis is a fish that feeds on mosquito larvae.
· Commonly introduced in ponds, lakes, and water bodies to reduce mosquito breeding.
Why is Malathion NOT an Anti-Larval Measure?
❌ Malathion is an adulticidal insecticide, not an anti-larval measure.
· It is a broad-spectrum organophosphate insecticide used to kill adult mosquitoes, not larvae.
· Used in fogging and spraying operations for vector control.